
B-63784EN/01 PROGRAMMING 19.AXIS CONTROL FUNCTIONS
- 767 -
- Chopping delay compensation function
When high-speed chopping is performed with the grinding axis, a servo
delay and acceleration/deceleration delay occur. These delays prevent
the tool from actually reaching the specified position.
The CNC measures the difference between the specified position and
the actual tool position, and performs chopping delay compensation to
compensate for the difference.
To compensate for this displacement, an amount of travel equal to the
distance between the upper and lower dead points, plus an appropriate
compensation amount, is specified. When a chopping command is
specified, the feedrate is determined so that the chopping count per unit
time equals the specified count. When the difference between the
displacement of the tool from the upper dead point and the
displacement of the tool from the lower dead point becomes smaller
than the setting of parameter No. 1881, after the start of chopping, the
control unit performs compensation.
When compensation is applied, the chopping axis moves beyond the
specified upper dead point and lower dead point, and the chopping
feedrate increases gradually.
When the difference between the actual machine position and the
specified position becomes smaller than the effective area setting
(parameter No. 1827), the control unit no longer applies compensation,
allowing the tool to continue moving at its current feedrate.
Point R
Upper dead point
L2 L4 L6
L1
L3 L5
Lower dead point
Time
Displacement between the tool and the upper dead point: L2, L4, L6
Displacement between the tool and the lower dead point: L1, L3, L5
Compensation starts when:
|L3 - L2| < (parameter No.1881)
When the following condition is satisfied, compensation is no longer applied,
and the tool continues to move at its current feedrate:
|L6| < effective area setting (parameter No.1827)